Dear Dr. Cohen,

Thank you so much for the comprehensive answers that you provide on this forum.

I know that I am asking a question that can only be answered in generalities, but here goes: All things being equal, are there significant differences in the life expectancy of some who contracts HIV at age 55 as opposed to 25? Is the immune system at an older age (in general) already somewhat compromised as a result of age? Or, do studies reveal that older folks who start on therapy have just as optimistic outcomes as their younger counterparts? I have not seen much research in this area?

One other question, if you don't mind: I have data that reveal that the duration from first HIV diagnosis to full-blown AIDS is generally 8-11 years. Once you do have AIDS, though, what is the normal life-expectancy?

Thanks for your time, attention, and acumen!

Sure thing.

We do have some information about these issues and in general the news is as you might expect. Our immune system is based primarily on some genetic "assumptions", including that as we age we are less likely to need "new" T cells, since in general after a few decades we likely have "seen" most of the environmental pathogens that are out there. And since HIV targets some of these cells that we might need, coming up with new ones is a bit harder for those who are older since the factory production is somewhat slowed down over time. But with all of the work that I am aware of, the differences appear relatively small - meaning that while we can find some statistical differences in populations, there are clearly some who are older and still effectively maintain a protective immune system. And so while the thymus is less functional even after age 40, it is not gone - just less. And so those over 40, and over 50 and indeed over 60 can do well. But it may take a bit longer for those cells to come back while on antivirals, or still leave someone a bit more vulnerable perhaps.

As for lifespan, it is important to know that the figures you mention come from the era where treatment was minimally effective. So if there is little to do in stopping HIV, it can take about a decade on average from initial infection to death from AIDS. However, we have since learned how to stop the damage done by HIV. Indeed, it is this success that has now led to enormous discussions about when to initiate treatment, since we know that treatment can be successful when started even at lower CD4 counts. And based on some of the most successful study examples we have, it is no longer absurd to consider the possibility that at least some with HIV will have a normal life span. The main challenge for those with viral suppression is now more the cumulative drug toxicity and how this may alter our life span. But here again we are making some progress -and so on balance things continue to improve, especially for those for whom the meds are effective and tolerable.

Which means you get to look forward to a longer life. Which means all those other things that happen become the issue. So yes it is important to eat well, stop smoking, and exercise and get annual check ups since the list of all that other stuff, like preventing heart disease and cancers can become the focus for those doing well... which is hopefully good news in a medical way...